Door-alarm



'T= NAGAYAMA.

DOOR ALARM.

APPLICATION EILED MAY 31. 1919.

Patented Dec. 30, 1919.

A firm/v5 rs rare ENT 0F 10E,-

TSUNETARO NAGAYAMA, OF I-I'II IO, TERRITORY OF HAWAII.

DOOR-ALARM.

To all whom it may concern:

Be it known that I, TSUNETARO NAGAYAMA, a subject of the Emperor of Japan, residing at Hilo, Territory of Hawaii, have invented new and useful Improvements in Door- Alarms, of which the following is a specification.

This invention relates to signals, particularly to audible alarms, and has for its object the provision of a device adapted for disposition upon a door frame and connected with the door whereby upon opening of the door from one side, an audible alarm will be sounded for apprising the occupants of a store or dwelling that the' door has been opened.

An important object is the provision of an alarm device of this character which is provided with means whereby upon opening the door from the inner side thereof, or rather the interior of the store or dwelling, as when a person passes out, the alarm may be rendered inoperative.

An additional object is the provision of a device of this character which will be simple and inexpensive in manufacture and installation, highly efficient in use, durable in service, and a general improvement in the art.

With the above and other objects and advantages in view, the invention consists in the details of construction to be hereinafter more fully described and claimed, and illustrated in the accompanying drawing, in Which- Figure 1 is a perspective view of a door frame and door showing my device applied thereto, v

Fig. 2 is a longitudinal sectional view on an enlarged scale through my device, and

Fig. 3 is a cross sectional view through the device.

Referring more particularly to the drawing, the letter A designates a door frame and B designates a door.

In carrying out my invention I provide, secured upon the door frame A, a plate 10 upon which is mounted a bell 11. Secured or formed upon the plate 10 is a rectangular casing 12 which is closed upon all sides except for the provision of an opening 13 at the side toward the bell 11. Secured within the casing 12 is a bracket 14 which has an offset portion 15 arranged in spaced relation to the plate10. J ournaled between the plate 10 and the offset portion 15 of the bracket .is a groo ed p y 9r roll r 6 about which Specification of Letters Patent.

Application filed May 31, 1919.

Patented Dec. 30, 1919.

Serial No. 300,903.

is trained a flexible member 17, such as a cable, which is provided at one end with a weight 18 and which is secured at its other end to the door B, it being understood that the casing 12 is provided with an opening 19 permitting the passage of the flexible member 17. The shaft 20 of the pulley or roller 16 has secured thereon exteriorly of the off set portion 15 of the bracket, a star wheel 21.

I further provide a bracket 22 secured upon the plate 10 having an ofiset portion 23 between which and the plate 10, is pivoted, as shown at 24, a lever 25 which is provided at one end with a striker 26 adapted to engage the bell 11 and which is provided at its other end with an angular portion 27 adapted for engagement between the arms of the star wheel 21. A coil spring 28 surrounds the pivot 24 and has one end secured to the lever 25 and its other end secured to the plate 10 for normally urging the lever 25 in such direction that the striker 26 will engage the bell 11. At its free end, the angular portion 27 of the lever 25 has connected therewith a flexible member 29 which passes through a hole 30 in the'bottom of the casing 12 and which is provided at its end with a finger engaging ring 31.

' In the operation of the device, the parts being assembled as shown and described, when the door B is opened from the outside thereof, a pull will be exerted upon the flexible member 17 which will result in rotation of the grooved pulley 16 and the star wheel 21 carried by the axle or shaft thereof. As the star wheel is rotated, the angular portion 27 of the lever 25 will be forced downwardly as the points of the arms of the star wheel pass over the angular portion, which will result in elevation of the striker 26. During rotation of the star wheel 21 the angular portion 27 will engage between the arms of the star wheel whereupon by virtue of the coil spring 28, the lever 25 will so move that the striker 26 will engage against the bell 11. As the pulley 16 and star wheel 21 rotate with appreciable speed during normal opening of the door, this alternate engagement and disengagement of the striker 26 with the bell will result in the giving of a ring, similar to the ring of an electric bell, thus apprising the occupants of the dwelling or store of the opening of the door.

Upon leaving the building it is designed that the person making his exit should grasp the finger engaging ring 31 and pull downwardly thereupon so as to move the angular portion 27 of the lever 25 out of the path of travel of the star wheel 21 so that the lever 25 and consequently the striker 26 will remain inoperative so as to avoid giving a signal.

From the foregoing description and a study of the drawing it will thus be apparent that I have provided a simple device adapted for association with a door and its frame whereby upon opening of a door an audible alarm will be sounded and it will also be apparent that means have been provided whereby the alarm may be rendered inoperative from the inner side of the door.

While I have shown and described the preferred embodiment of my invention, it is of course to be understood that I reserve the right to make such changes in the form, construction, and arrangement of parts as will not depart from the spirit of the inven tion or the scope of the subjoined claims.

Having thus described my invention, I claim 1. An alarm device comprising a plate, a bell secured upon said plate adjacent one end thereof, a casing upon the other end of said plate and provided in its wall to ward said bell with an opening, a bracket secured within said casing and having an offset portion, a grooved pulley having an axle journaled in the offset portion of said bracket and said plate, a flexible member trained about said pulley and provided with a weight, a star wheel secured upon the axle of said pulley'exteriorly of said ofiset portion of said bracket and disposed within said casing, a second bracket secured upon said plate within said casing in spaced relation to said first named bracket and having and offset portion, a lever pivoted between said plate and the ollset portion of said second named bracket and having one end projecting through the opening in said casing wheel.

2. A door alarm device comprising a plate adapted to be secured upon a door frame, a bell mounted upon the plate, a vertically disposed pulley journaled upon the plate and carrying a toothed wheel, means associated with a door for rotating said pulley upon opening the door, a lever pivoted upon the plate and having one end provided with a striker normally engaging the bell and having its other end formed to provide an angular portion conformingly engaging between the teeth of said wheel, and means for holding said angular portion out of the path of movement of the wheel.

TSUNETARO NAGAYAMA.

Witnesses FRED PATTERSON, YOSHIKATSU NAKAYHMA, 

